In Idaho several different types of public entities own and/or operate regulated municipal stormwater systems. These regulated public entities include cities and counties; local highway districts, and the Idaho Transportation Department (ITD); colleges and universities; drainage districts which convey urban storm water runoff; and others.
Some Idaho public entities' stormwater discharges have had federal NPDES permit coverage since 2000 (i.e., Boise and Garden City urbanized areas), other areas' discharges have been covered by federal permits since 2007 and later (i.e., Pocatello, Idaho Falls, Coeur d'Alene, Post Falls, Middleton, Nampa, and Caldwell urbanize areas). And the list of public entities in growing urbanized areas that require permit coverage continues to expand (i.e., Lewiston and Moscow).
Stormwater permits issued to cities typically include Stormwater Management Plans for the control of construction site runoff, permanent stormwater management controls for new development and redevelopment, good housekeeping and pollution prevention measures for existing stormwater infrastructure, removal and reduction of unauthorized and illegal stormwater discharges, education outreach and public involvement for water quality protection, discharge water quality monitoring, and, in some cases, special conditions for discharges to impaired surface waters.
Section 402(p)(3) of the Clean Water Act states that municipal permits for stormwater discharges "shall require controls to reduce pollutant discharges to the maximum extent practicable," including best management practices (BMPs) and other provisions as determined to be appropriate for pollutant control. Under this provision, the permitting authority has the discretion to include requirements for reducing pollutants in stormwater necessary for compliance with water quality standards.
EPA has long maintained that water quality-based BMPs, implemented through iterative processes, are appropriate for the control of pollutants in municipal stormwater and may require expanded or more specific BMPs in permits when they are necessary to achieve stormwater waste load allocations and attain water quality standards.
Last year the Ninth Circuit Court approved a settlement agreement requiring the EPA to revise the rules that govern Phase II stormwater permits for small MS4s. These new rules are due by November 17, 2016.
The September 2015 settlement stems from a 2003 decision by the Ninth Circuit Court of Appeals where the court told EPA to “take appropriate action” to address the “procedural issues” with its small municipal stormwater policy and related Phase II stormwater rules. In 2004 the EPA issued interim guidance in response to the court’s remand, but did not pursue a formal rulemaking.
In response to the 2015 settlement the EPA issued proposed revised rules in January 2016. The proposed rules require small cities to detail their strategies for controlling stormwater runoff before they can get permit coverage, and require permitting authorities to provide the public with the opportunity to review, submit comments, and request a public hearing on the proposed strategies. The permitting authorities must then make a final determination on Clean Water Act compliance – all before authorizing the stormwater discharge(s).
Meanwhile, back in Idaho, we are anticipating a public review draft of the Idaho Phase II Municipal Stormwater General Permit soon. Similar to the combined single general permit for Phase 1 and Phase II published last April, the pending Phase II general permit is expected to represent a shift from how EPA has been doing municipal stormwater permitting (i.e., going from individual permits to a single general permit). EPA is expected to propose waterbody-specific measures necessary to comply with Idaho Total Maximum Daily Loads (TMDLs), including monitoring, assessment activities, and other additional pollutant-specific controls.
Comments were submitted to Idaho DEQ by AIC on the EPA Region 10 pre-draft municipal stormwater permits on September 14, 2016.